Foaming soap dispensers and methods

ABSTRACT

A soap dispenser can be configured to dispense an amount of foam soap. In some embodiments, the dispenser can include a venturi device with an air inlet and a soap inlet. In certain implementations, the dispenser can include a flexible impeller pump. In some such embodiments, the pump can be configured to draw liquid soap through the soap inlet of the venturi device and air through the air inlet of the venturi device. The soap and air can mix to form foam, which can be drawn into the pump and dispensed via a nozzle in communication with the pump. In some embodiments, the dispenser includes a screen, which can modify the texture of the foam.

CROSS-REFERENCE TO RELATED APPLICATIONS

This present application claims priority benefit under 35 U.S.C. §119(e) to U.S. Provisional Application No. 61/595,629, filed Feb. 6, 2012, entitled “FOAMING SOAP DISPENSERS AND METHODS,” which is hereby incorporated by reference in its entirety.

BACKGROUND

1. Field

The present disclosure relates to dispensing devices, and some embodiments are particularly related to dispensers configured to dispense foam soap.

2. Description of the Related Art

Users of modern public washroom facilities increasingly desire that each of the fixtures in the washroom operate automatically without being touched by the user's hand. This is important in view of increased user awareness of the degree to which germs and bacteria may be transmitted from one person to another in a public washroom environment. Today, it is not uncommon to find public washrooms with automatic, hands-free operated toilet and urinal units, hand washing faucets, soap dispensers, hand dryers, and door opening mechanisms. This automation allows the user to avoid touching any of the fixtures in the facility, and therefore lessens the opportunity for the transmission of disease-carrying germs or bacteria resulting from manual contact with the fixtures in the washroom.

SUMMARY

Certain aspects of this disclosure are directed toward a soap dispenser including a housing, a reservoir, an aspirator, a pump, and a discharge nozzle. The reservoir can be at least partly contained in the housing and configured to store liquid soap. The aspirator can include a first inlet, a second inlet, and an outlet. The first inlet can be in fluid communication with the reservoir, and the second inlet can be in fluid communication with the ambient environment. The outlet can be in fluid communication with the first and second inlets via a channel. The pump can be disposed in the housing and can include a body and an impeller. The impeller can be disposed in an inner cavity of the body, and the inner cavity can be in fluid communication with the aspirator outlet. The pump can be configured to encourage a flow of liquid soap from the reservoir through the first inlet and to encourage a flow of air from the ambient environment through the second inlet. The channel of the aspirator can be configured to encourage mixing of the flows of liquid soap and air to generate soap foam. The discharge nozzle can be configured to discharge a portion of the soap foam. The discharge nozzle can be in fluid communication with the inner cavity of the pump body.

The features disclosed in this specification can be included in any embodiments. The soap dispenser can include a valve disposed along a flow path between the reservoir and the aspirator. The aspirator can include a first tapered portion in fluid communication with the channel and a second tapered portion in fluid communication with the channel. The first inlet and the outlet can be generally axially aligned. A first inlet diameter can be larger than a second inlet diameter. A first inlet diameter can be larger than a channel diameter. The second inlet can be generally centered on an axis that is substantially perpendicular to the longitudinal axis of the channel. The impeller can include a central body portion and a plurality of flexible arms. The impeller can include a bore. In certain aspects, the soap dispenser can include an actuation mechanism connected to the impeller bore. The impeller can include a central body portion and a plurality of flexible arms. In certain aspects, each of the flexible arms can include a rounded protrusion. The impeller can include a central body portion and a plurality of flexible arms. The inner cavity can be configured to bend at least one of the flexible arms more than another one of the flexible arms. The inner cavity can have a generally eccentric-circular shape. The pump can be configured to generate a negative pressure that is less than a pressure at the aspirator outlet. The pump can include an inlet pocket near a pump inlet and an outlet pocket near a pump outlet. The inlet pocket can be larger than the outlet pocket. The pump can include a pocket configured to transition between a first configuration and a second configuration. The pocket can be larger in the first configuration than in the second configuration. The soap dispenser can include a flow-enhancing member in fluid communication with the inner cavity of the pump body and disposed downstream from the pump. The flow-enhancing member can be a screen. The flow-enhancing member can be configured to provide a back pressure. The discharge nozzle can be a duckbill valve. The soap dispenser can include a holding chamber disposed downstream of the aspirator. The holding chamber can be configured to store the soap foam for a period of time.

Certain aspects of this disclosure are directed toward methods of dispensing foaming liquid soap from a soap dispenser. Some embodiments of the methods can include drawing a flow of liquid soap from a reservoir and through a first inlet of an aspirator. Certain embodiments include drawing a flow of ambient air through a second inlet of the aspirator. Some variants of the methods can include generating soap foam in a channel of the aspirator. According to some variants, the methods can include drawing the soap foam from an aspirator outlet and through an inlet of a pump. The pump can include a body and an impeller, and the impeller can be disposed in an inner cavity of the body. In some embodiments, the methods can include discharging a portion of the soap foam from a nozzle.

The method steps disclosed in this specification can be used in any embodiments of the methods. The methods can include drawing the soap foam through an outlet of the aspirator and into a holding chamber. Some embodiments of the methods can include storing the soap foam in the holding chamber for a period of time. Drawing the flow of liquid soap from the reservoir and through the first inlet can include drawing the flow of liquid soap through a valve. The methods can also include driving the impeller. In certain aspects, driving the impeller can include moving a pocket between a first configuration and a second configuration. The pocket can be larger in the first configuration than in the second configuration. In certain aspects, driving the impeller can include moving each of the flexible arms between a first configuration and a second configuration. Each of the flexible arms can be more bent in the first configuration than in the second configuration. The methods can include generating a negative pressure within the aspirator channel relative to ambient. The methods can include generating a region of pressure near the second inlet that is less than a region of pressure near the first inlet. The methods can also include generating a negative pressure within the inner cavity relative to ambient. The methods can include generating a pressure within the inner cavity that is less than the pressure at the aspirator outlet. The methods can include discharging the soap foam from an outlet of the pump and through a flow-enhancing member. Discharging the soap foam through the flow-enhancing member can include generating a back pressure.

For purposes of summarizing the disclosure, certain aspects, advantages and features of the inventions have been described herein. It is to be understood that not necessarily any or all such advantages can be achieved in accordance with any particular embodiment of the inventions disclosed herein.

BRIEF DESCRIPTION OF THE DRAWINGS

Certain features, aspects, and advantages of the subject matter disclosed herein are described below with reference to the drawings, which are intended to illustrate and not to limit the scope of the disclosure. Various features of different disclosed embodiments can be combined to form additional embodiments, which are part of this disclosure. No structures, features, steps, or processes are essential or critical; any can be omitted in certain embodiments. The drawings comprise the following figures:

FIG. 1 is a schematic diagram illustrating an embodiment of a foam soap dispenser;

FIG. 2A is a schematic diagram illustrating another embodiment of a foam soap dispenser including a venturi device, pump, mesh, and dispensing assemblies;

FIG. 2B is a cut-away top view of an embodiment of the pump of FIG. 2A;

FIG. 3 is a perspective view of a venturi device and an impeller pump;

FIG. 4 is a perspective view of the venturi device of FIG. 3;

FIG. 5 is a perspective view of the venturi device of FIGS. 3 and 4;

FIG. 6 is a cross-sectional view of the venturi device of FIG. 5 taken along line 6-6;

FIG. 7 is an end view of the venturi device of FIGS. 3 and 4;

FIG. 8 is a perspective view of a flexible impeller mechanism; and

FIG. 9 is a perspective view of a flexible impeller pump.

DETAILED DESCRIPTION

FIG. 1 schematically illustrates an embodiment of a foaming soap dispenser 10 that can include various features and embodiments of the subject matter disclosed herein. Certain features and embodiments of the subject matter are disclosed in the context of a foam soap dispenser 10 because they have particular utility in this context. However, the subject matter disclosed herein can be used in many other diverse contexts and environments of use. For example, some or all of the subject matter disclosed herein can be used in other types of pumps, dispensers, battery-powered devices, or even any other electric devices. Those of ordinary skill in the art will recognize, from the description set forth below, many of the other environments of use in which the subject matter can be used, although all of those environments are not described herein.

The soap dispenser 10 includes a housing 12. The housing 12 can be configured to support a liquid handling system 14. The liquid handling system 14 can include a reservoir 16, a pump 18, and a discharge assembly 20. Some embodiments of the liquid handling system 14 include an air inlet conduit 70 and an aspirator, such as a venturi device 85. In some embodiments, the inlet conduit 70 is configured to intake air directly from the ambient environment. In some embodiments, the inlet conduit 70 is configured to intake air indirectly from the ambient environment, such as by intaking air within the housing 12.

The reservoir 16 can be any type of container, such as a vessel, bag, balloon, or otherwise. In the illustrated embodiment, the reservoir 16 is configured to contain a volume of liquid soap, such as liquid soap for hand washing. In some embodiments, the reservoir 16 can include a lid 22 configured to form a seal at the top of the reservoir 16 for maintaining the liquid soap L within the reservoir 16. In some embodiments, the lid 22 can include an air vent (not shown), so as to allow air to enter the reservoir 16 as the level of liquid soap L falls within the reservoir 16.

The reservoir 16 can include an outlet 24. In certain embodiments, the outlet 24 can comprise a conduit extending from the reservoir 16. In some embodiments, the outlet 24 can comprise an opening in the lower portion of the reservoir 16. In certain implementations, the outlet 24 can place the reservoir 16 in fluid communication with an aspirator.

In some embodiments, the aspirator can be an eductor-jet pump or a filter pump, or a venturi device 85 as illustrated, which can include an air inlet conduit 70 and an outlet 77. The air inlet conduit 70 can be any type or diameter of conduit, so as to allow air to enter the venturi device 85. The air inlet conduit 70 can include a first end 70 a and a second end 70 b. The first end 70 a can be connected with the venturi device 85. In some embodiments, the second end 70 b of the air inlet conduit 70 is disposed outside the reservoir 16 (e.g., in communication with the ambient environment). In some embodiments, the second end 70 b of the air inlet conduit 70 is positioned in the reservoir 16 (e.g., above the fill level of liquid soap). In some variants, the air inlet conduit 70 includes a one-way valve (e.g., a flapper valve, duckbill valve, or otherwise) that is configured to inhibit air and/or soap from exiting the venturi device 75 via the air inlet conduit 70. As shown, the venturi device 85 can be connected to the pump 18 via the outlet 77.

The pump 18 can be configured to draw a flow of soap from the outlet 77 and encourage the soap to flow through the conduit 26. In some embodiments, the pump 18 can be disposed in the reservoir 16. In certain such embodiments, the pump 18 can be automatically primed due to the force of gravity drawing soap into the pump 18. In some implementations, the pump 18 is positioned elsewhere within the housing 12. For example, in some configurations, the pump 18 is positioned above at least part of the reservoir. In certain cases, a fluid conveyor, such as a worm-screw or an auger, or the like, is configured to deliver liquid soap to the pump 18.

As illustrated, the pump 18 can be connected to the discharge assembly 20 via the conduit 26. The discharge assembly 20 can include a flow-enhancing member (e.g., a screen 86), and tubing 87, and a discharge nozzle 28. In some embodiments, the screen 86 is disposed in the flow path of the soap between the pump 18 and the nozzle 28. In some embodiments, the screen 86 is disposed elsewhere, such as downstream of the discharge nozzle 28.

In certain implementations, the discharge nozzle 28 is configured to dispense foam and inhibit undesired dripping of soap (liquid or foamed) after a dispensing cycle ends. For example, the discharge nozzle 28 can include a one-way valve, such as a duckbill or pin valve, that is configured to close after an amount of foam has been dispensed. The size of the discharge nozzle 28 can be determined to provide the appropriate flow rate and/or resistance against flow of foam soap from the pump 18.

In some embodiments, the nozzle 28 can be disposed at a location spaced above the lower portion of the housing 12 (e.g., at or near the top of the housing) so as to make it more convenient for a user to place a hand or other body part under the nozzle 28. For example, in some embodiments, the nozzle 28 can be disposed on a vertical portion of the housing 12, so that the force of gravity encourages the foam soap to shear from the nozzle 28 after dispensation. However, other configurations can also be used.

The pump 18 can be driven or otherwise operated by an actuator 34. In certain embodiments, the actuator 34 is an AC or DC electric motor, stepper motor, server motor, solenoid, stepper solenoid, or any other type of actuator. In some implementations, the actuator 34 is connected to the pump 18 with a transmitter device 50. For example, the transmitter device 50 can include any type of gear train or any type of flexible transmitter assembly (e.g., belt, chain, or otherwise).

In certain embodiments, the pump 18 is controlled by an electronic control unit 46. The ECU 46 can include one or a plurality of circuit boards providing a hard wired feedback control circuit, a processor and memory devices for storing and performing control routines, or any other type of controller. In some embodiments, the ECU 46 can include an H-bridge transistor/MOSFET hardware configuration which allows for bidirectional drive of an electric motor, and a microcontroller such as Model No. PIC16F685 commercially available from the Microchip Technology Inc., and/or other devices.

Some embodiments of the dispenser 10 can include a power supply 60. Typically, the power supply 60 is configured to power the ECU 46 and/or the actuator 34. The power supply 60 can be, for example, a battery or can include electronics for accepting AC or DC power.

The dispenser 10 can also include a user input device 52. The user input device 52 can be any type of device allowing a user to input a command into the ECU 46. For example, the input device 52 can be a button that a user can depress to transmit a command to the ECU 46. In some embodiments, the ECU 46 can be configured to actuate the actuator 34 to drive the pump 18 any time the input device 52 is activated by a user. The ECU 46 can also be configured to provide other functions upon the activation of the input device 52, such as signaling the dispenser to dispense a predetermined amount (e.g., an amount suitable for washing cookware) or a continuous flow of foam soap.

FIG. 2A provides a schematic illustration of the liquid handling system 14, discharge assembly 20, and pump 18. As previously described, the liquid handling system 14 can include the venturi device 85. The venturi device 85 can have a first inlet 75, a second inlet 79, and an outlet 77. The outlet 77 can be in fluid communication with the first and second inlets 75, 77. According to some embodiments, the venturi device 85 can be configured such that the first inlet 75 and the second inlet 79 each receive an inflow of liquid soap, air, or any combination of liquid soap and air.

In some embodiments, the pump 18 can draw liquid soap into the venturi device 85 via the first inlet 75. For example, in some embodiments, the pump 18 can create a negative pressure of the venturi device 85, compared to ambient. In certain variants, compared to ambient, a negative pressure of at least about 0.3 psi is created within the venturi device 85. In some embodiments, the pump 18 generates a negative pressure of less than or equal to about 0.5 psi inside of the venturi device 85, compared to ambient. In some embodiments, the pump 18 generates a negative pressure of at least about 0.5 psi inside of the venturi device 85, compared to ambient.

In some embodiments, the negative pressure within the venturi device 85 can result in air being drawn in through the second inlet 79. As discussed in further detail below, the venturi device 85 can include a necked portion, or a region in which a cross-sectional width is less than the cross-sectional widths of nearby regions, which can further encourage the drawing of air into the venturi device 85 via the second inlet 79. In some embodiments, the pump 18 can encourage both liquid soap and air to be pulled through the venturi device 85 toward the outlet 77, such as via the first and second inlets 75, 77, respectively. In certain implementations, the liquid soap and the air mix as they pass through the venturi device 85, thereby forming soap foam. For example, the flow of liquid soap and the flow of air can turbulently engage to produce soap foam.

Some embodiments of the dispenser 10 include a chamber 65 disposed between the venturi device 85 and the pump 18. The dispenser 10 can include a conduit 27 which provides fluid communication between the venturi device 85 and the chamber 65. In some implementations, the chamber 65 can be configured to store foam produced by the venturi device 85. For example, some variants of the chamber 65 can receive and/or store an overflow of foam (e.g., more foam than the venturi device can contain) from the outlet 77 of the venturi device 85. In certain embodiments, the volume of the chamber 65 can be equal to or greater than the volume of the venturi device 85 and/or the pump 18. In some embodiments, the chamber 65 and the venturi device 85 are separate components. In other embodiments, the chamber 65 can be incorporated into, and/or monolithically formed with, the venturi device 85 so that the chamber 65 and venturi device 85 form a unitary component. Certain implementations of the chamber 65 can allow for further mixing of soap and air after the above-described initial mixing occurs within the venturi device 85. In some embodiments, the flow of the soap foam pauses in the chamber 65 for a period of time (e.g., greater than or equal to about 1 second). For example, in some variants, the flow of the soap foam is generally stationary in the chamber 65 before proceeding toward inlet 25 of the pump 18. In some implementations, the volume of soap foam entering the chamber 65 (e.g., the volume of soap foam exiting the venturi device 85) is greater than or approximately equal to the volume of soap foam exiting the chamber 65 (e.g., the volume of soap foam entering the pump 18).

According to some embodiments, an outlet 25 provides fluid communication between the venturi device 85 and/or chamber 65 and the pump 18. Various types of pumps can be employed. For example, in certain embodiments, the pump 18 is a gear pump. In some embodiments, the pump 18 can comprise a flexible impeller pump, such as is illustrated in FIG. 2B. Certain embodiments of a flexible impeller pump generally include a pump body 255 with an inner cavity 252 that houses a flexible impeller 250. In some embodiments, the flexible impeller 250 can comprise a central body portion 258 and a plurality of flexible arms 257 extending from the central body portion 258. Typically, the flexible arms 257 are made of a resilient material, such as rubber, plastic, or silicone. As discussed in further detail below, in certain orientations, the flexible arms 257 are bent, compressed, or otherwise moved or changed in shape, by the body 255, thereby drawing the soap in through a pump inlet 253 and discharging the soap out through a pump outlet 254. The pump 18 can be configured to engage with the conduit 26 via the pump outlet 254.

As discussed above, the conduit 26 can include one or more flow-enhancing members, such as mesh screens 86. The one or more screens 86 can be made of any material, such as a material that resists corrosion in the presence of water, such as plastic, rubber, stainless steel, or any other similar material. The mesh-size of the screen 86 (e.g., the size of the holes defined by the structure of the screen) can be chosen so as to provide a desired flow characteristic of foam discharged through the nozzle 28, in the downstream direction. For example, a screen 86 can be used to provide a back pressure sufficient to briefly hold back an initial flow of foam as it is discharged from the nozzle 28 such that the foam that is first discharged has a shape that matches the shape of the nozzle 28. In some embodiments, without such a screen or backpressure-creating device, a pump can occasionally discharge an initial amount of foam that has an outer diameter or shape that does not match the nozzle 28. In some embodiments, the nozzle 28 can comprise a duckbill valve or some other low-pressure valve.

FIGS. 3 and 4 show a partial embodiment of the liquid-handling system 14. In the embodiment shown, the reservoir 16 and outlet 24 are illustrated as a liquid soap supply 17 and a tube adaptor 29. Of course, in other implementations, the dispenser 10 includes the reservoir 16 and outlet 24, as discussed above. The liquid soap supply 17 can include a first tube 33 and a second tube 35 with a disconnection-resistant valve 31 connected therebetween (e.g., with barbed fittings). The valve 31 can be configured to control the flow of liquid soap passing through the liquid soap supply 17. The tube adaptor 29 can be configured to connect with the second tube 35 and the venturi device 85. For example, one end of the adaptor 29 can be configured to receive the second tube 35 and a second end of the adaptor 29 can flare radially outward to receive a portion of the venturi device 85.

With regard to FIGS. 5-7, an embodiment of the venturi device 85 is shown. As previously noted, the venturi device 85 can comprise the first inlet 75, second inlet 79, and outlet 77. The first inlet 75 can be configured to engage with a source of liquid soap (e.g., the reservoir 16), an air source, or both. The second inlet 79 can be configured to engage with an air source, a source of liquid soap, or both. The outlet 77 can be configured to discharge the flow of the inlets 75, 79. In some embodiments, the first inlet 75 has a first inner diameter D1 and the outlet 77 has a second inner diameter D2. In some embodiments, D1 is approximately equal to D2. In certain implementations, D1 and/or D2 are at least about 1.0 mm and/or equal to or less than about 20 mm. In some versions, D1 and/or D2 are at least about 2.0 mm and/or equal to or less than about 10 mm. In certain embodiments, D1 and/or D2 are at least about 2.5 mm and/or equal to or less than about 5.0 mm. Further, in some embodiments, D1 and/or D2 is approximately 3.0 mm. In some arrangements, D2 is greater than D1. For example, D2 can be at least about 1.1, about 1.7, or about 2.0 or otherwise, times the size of D1. Such a configuration can, for example, provide additional through-put for foam via the outlet 77. In certain embodiments, the outlet 77 of the venturi device 85 can be configured to engage with an inlet 253 of the pump 18.

In some embodiments, the first inlet 75 communicates with a first tapered portion 81 and the outlet 77 communicates with a second tapered portion 89. A channel 83 can fluidly connect the first and second tapered portions 81, 89. The channel 83 can have an inner diameter D3. Typically, the inner diameter D3 is less than each of the inner diameters D1 and D2. For example, D3 can be less than or equal to about ⅛, about ½, about ⅞ or otherwise, the size of D1 and/or D2. The venturi device 85 can have a generally hour-glass shape in cross-section. In some embodiments, the interior shape can facilitate a change in pressure as fluid flows through the venturi device 85, as discussed in further detail below. In some embodiments, the first tapered portion 81 tapers from D1 to D3 and the second tapered portion tapers from D2 to D3. In some versions, D3 is at least about 0.5 mm and/or equal to or less than about 10 mm. In certain embodiments, D3 is at least about 0.75 mm and/or equal to or less than about 2.5 mm. According to some configurations, D3 is approximately 1.0 mm. The first tapered portion 81 and/or the second tapered portion 89 can each taper generally linearly or generally non-linearly (e.g., can be generally curved). In some embodiments, generally one of the portions 81, 89 tapers generally linearly, and the other of the tapered portions 81, 89 tapers non-linearly.

In certain implementations, the channel 83 is also fluidly connected with the second inlet 79. For example, as shown, the second inlet 79 can be positioned on a side of the venturi device 85. In some embodiments, the second inlet 79 is disposed substantially perpendicular to a longitudinal axis of the channel 83. In some instances, the second inlet 79 is spaced apart from the first and second tapered portions 79. In certain implementations, the second inlet 79 is generally non-tapered.

The second inlet can have an inner diameter D4. In certain versions, D4 is at least about 0.5 mm and/or less than or equal to about 5.0 mm. In some instances, D4 is about 2.0 mm. In some embodiments, D4 is less than D1 and/or D2. For example, D4 can be less than or equal to about ⅛, about ½, or about ⅞ or otherwise, the size of D1 and/or D2. In certain implementations, D4 is at least about 0.8 times and/or less than or equal to about 1.3 times the size of D3. In some embodiments, D4 is about equal to D3.

Generally, when fluid (e.g., liquid soap) is flowing though the venturi device 85 from the first inlet 75 to the outlet 77, the first inlet has a pressure of P1 and the outlet 77 has a pressure of P3. As the fluid flows through the first tapered portion 81 toward the reduced diameter of the channel 83, the fluid generally increases in velocity. Such an increase in velocity generally results in a reduction of pressure, thereby forming a region of low pressure P2 in the vicinity of the second inlet 79. This low pressure P2 can cause fluid (e.g., air) to be pulled into the venturi device 85 via the second inlet 79, which can result in a mixing of the fluid entering through the first inlet 75 and the fluid entering the second inlet 79.

For example, in some embodiments, the pump 18 will create a pressure differential that can pull liquid soap through the first inlet 75, through the venturi device 85, and out of the outlet 77. As the liquid soap passes through the first tapered portion 81 and the channel 83 the velocity of the liquid soap increases due to the decreased diameter, thereby generating the low pressure P2 is created in the channel 83. The low pressure P2 can cause air to be drawn in through the second inlet 79. The air and liquid soap can then mix in the venturi device 85 and the mixture can exit the venturi device 85 via the outlet 77, generally in the form of soap foam. In some embodiments, air enters the venturi device 85 via the inlet 75 and liquid soap enters the venturi device 85 through the second inlet 79.

Various foams can be produced with the venturi device 85. According to some configurations, the ratio of soap to air can be at least approximately 3:1 and/or less than or equal to approximately 8:1, depending on, for example, the type of soap used and the desired qualities of the foam. In some embodiments, the ratio of soap to air can be less than about 3:1. In other embodiments, the ratio of soap to air could be greater than about 8:1.

FIGS. 8 and 9 show an embodiment of the flexible impeller pump 18. As previously noted, the flexible impeller pump 18 can include the pump body 255 that is configured to receive the flexible impeller 250, which in turn can comprise the central hub 258 with a plurality of flexible arms 257 extending therefrom. In some embodiments, the outside diameter of the flexible impeller 250 (including the arms 257) can be at least about: 8.0 mm, 12.0 mm, 14.0 mm, or otherwise. In some embodiments, the length of the flexible arms 257 can be at least about: 1.5 mm, 3.5 mm, 5.0 mm, or otherwise.

In some implementations, the flexible arms 257 have ends 259 that are functionally shaped to enhance the sealing contact between the flexible arms 257 and the pump body 255. For example, in the embodiment shown, the ends 259 have rounded protrusions. The shape of the flexible arms 257 can facilitate the movement of the pump, such as by reducing the likelihood of the arms becoming caught or snagged on the pump body 255.

The pump body 255 can include an inner cavity 252. In some embodiments, the inner cavity 252 has a generally elliptical, generally eccentric-circular, or other non-circular shape. In certain such instances, some portions of the inner cavity 252 are nearer to the central hub 258 than other portions of the inner cavity 252. For example, in some embodiments, the inner cavity can have an elliptical shape having a major axis (e.g., of at least approximately: 10 mm, 14 mm, 17 mm, or otherwise) and a minor axis (e.g., of about: 8 mm, 10 mm, or 13 mm, or otherwise). In some instances, the portions of the pump body 255 that form the minor axis are closer to the central hub 258 of the flexible impeller 250 than the portions of the pump body 255 that form the major axis.

In some embodiments, the flexible impeller 250 can be housed within the inner cavity 252 of the pump body 255. The impeller 250 can be operably connected with the actuator 34, such that the actuator 34 can rotate the impeller 250 relative to the pump body 255. For example, the impeller 250 can include a bore 260 that is configured to couple with the transmitter device 50 (e.g., a shaft), which in turn connects with the actuator 34. In some embodiments, the actuator 34 can rotate the impeller 250. For example, the actuator 34 can be configured to rotate the impeller at a speed of at least about 2,000 RPM and/or equal to or less than about 3,000 RPM. According to some configurations, the thickness T1 of the flexible impeller 250 can be such that the top surface of the flexible impeller 250 can be substantially flush with the top surface of the pump body 255. In some implementations, the top surface of the flexible impeller 250 is recessed from top surface of the pump body 255 so as to allow space for another component, such as a gasket.

In some embodiments, the inner cavity 252 can be shaped or otherwise configured to cause bending in the flexible arms 257 as the central body portion 258 rotates relative to the pump body 255. For example, when the flexible arms 257 contact the portions of the inner cavity 252 that are nearer to the central hub 258 of the flexible impeller 250, the flexible arms 257 deflect, move, compress, other otherwise change in shape, more than when the arms contact the portions of the inner cavity 252 that are farther from the central hub 258 of the flexible impeller 250. For example, in a generally elliptical inner cavity 252, the arms 257 in contact with the portion of the inner cavity at the minor axis of the ellipse can be bent more than the arms in contact with the portion of the inner cavity at the major axis of the ellipse.

Typically, the flexible arms 257 of the impeller 250 are configured to contact the inner cavity 252 of the pump body 250. In various configurations, a plurality of pockets can be formed between the impeller 250 and the inner cavity 252. In some implementations, each of the pockets can be formed between two of the arms 257, the central body 258, and the inner cavity 252. In certain embodiments, at least one of the pockets can be variably-sized, such as during the movement (e.g., rotation) of the pump. For example, as illustrated in FIGS. 2A and 8, an inlet pocket 251 can be formed in the vicinity of the pump inlet 253 and an outlet pocket can be formed in the vicinity of the pump outlet 254. In some embodiments, the inlet pocket 251 can be larger than the outlet pocket 256.

In some embodiments, the size of at least one pocket will vary as the impeller 250 spins. As the impeller 250 spins, the pocket moves around the periphery of the inner cavity 252. According to some embodiments, as illustrated in FIGS. 2 and 9, a pocket that starts as an inlet pocket 251 will gradually change in size as it moves about the inner cavity 252. For example, the size of the pocket can remain relatively constant until the pocket approaches the outlet 254. As the pocket approaches the outlet 254, the radius of the interior walls of the inner cavity 252 can decrease which can cause the flexible arms 257 defining the pocket to bend and reduce the size of the pocket. This reduction in size of the pocket can increase the pressure within the pocket, which in turn can eject the foam within the pocket into the pump outlet 254 as the pocket passes the outlet 254.

As the pocket continues to move about the inner cavity 252, an increase in the radius of the inner cavity 252 can cause the arms 257 to unbend or to otherwise return to an initial state or condition in the vicinity of the inlet 253 and thereby increase the size of the pocket. As the pocket expands and passes the inlet 253, a decrease in pressure (e.g., a vacuum) can be created within the pocket, which can pull foam into the pocket from the inlet 253. In some embodiments, the pump 18 generates a negative pressure that is less than the pressure at the outlet 77 of the venturi device 85 (e.g., ambient). In various embodiments, foam from the venturi device 85 is draw into the pocket in the pump 18. In certain implementations, the pump 18 generates a negative pressure (relative to the pressure in at the outlet 77) of at least about 0.2 psi and/or less than or equal to about 2.0 psi. In some instances, the pump 18 generates a negative pressure of at least about 0.4 psi and/or less than or equal to about 1.0 psi. In some embodiments, the pump 18 generates a negative pressure of about 0.5 psi.

Accordingly, as the impeller 250 spins within the pump body 255, foam can be drawn from the venturi device 85 into the pump body 255. Further, the foam can be discharged from the pump body 255 into the conduit 26 for dispensation via the nozzle 28 as desired.

Although the dispenser has been disclosed in the context of a certain embodiments and examples, it will be understood by those skilled in the art that the dispenser extends beyond the specifically disclosed embodiment to other alternative embodiments and/or uses of the dispenser and obvious modifications and equivalents thereof. In addition, while several variations of the dispenser have been shown and described in detail, other modifications, which are within the scope of this disclosure, will be readily apparent to those of skill in the art. For example, some embodiments of the dispenser are configured to draw air through the first inlet of the venturi device and soap through the second inlet of the venturi device. Further, some embodiments of the dispenser are configured to dispense foam other than soap foam, such as lotion foam, fire-suppressant foam, insulation foam, and otherwise. Moreover, in certain embodiments, the air inlet of the venturi device can be selectively closed (e.g., by a valve, movable door, other otherwise), thereby permitting the dispenser to selectively dispense either liquid soap or foam soap based on whether liquid soap and air or only liquid soap are allowed to enter the venturi device. It is also contemplated that various combination or sub-combinations of the specific features and aspects of the embodiments or variations may be made and still fall within the scope of this disclosure. It should be understood that various features and aspects of the disclosed embodiments can be combined with or substituted for one another in order to form varying modes of the dispenser. Thus, it is intended that the scope of the dispenser herein-disclosed should not be limited by the particular disclosed embodiments described above, but should be determined only by a fair reading of the claims that follow. 

1. A soap dispenser comprising: a housing; a reservoir configured to store liquid soap; an aspirator comprising a first inlet, a second inlet, and an outlet, the first inlet in fluid communication with the reservoir, the second inlet in fluid communication with the ambient environment, the outlet in fluid communication with the first and second inlets via a channel; a pump disposed in the housing and comprising a body and an impeller, the impeller disposed in an inner cavity of the body, the inner cavity in fluid communication with the aspirator outlet, the pump configured to encourage a flow of liquid soap from the reservoir through the first inlet and to encourage a flow of air from the ambient environment through the second inlet, the channel of the aspirator configured to encourage mixing of the flows of liquid soap and air to generate soap foam; and a discharge nozzle configured to discharge a portion of the soap foam, the discharge nozzle in fluid communication with the inner cavity of the pump body.
 2. The soap dispenser of claim 1, further comprising a valve disposed along a flow path between the reservoir and the aspirator.
 3. The soap dispenser of claim 1, wherein the aspirator further comprises a first tapered portion in fluid communication with the channel and a second tapered portion in fluid communication with the channel.
 4. The soap dispenser of claim 1, wherein the first inlet and the outlet are generally axially aligned.
 5. The soap dispenser of claim 1, wherein a first inlet diameter is larger than a second inlet diameter.
 6. The soap dispenser of claim 1, wherein a first inlet diameter is larger than a channel diameter.
 7. The soap dispenser of claim 1, wherein the second inlet is generally centered on an axis that is substantially perpendicular to the longitudinal axis of the channel.
 8. The soap dispenser of claim 1, wherein the impeller comprises a central body portion and a plurality of flexible arms.
 9. The soap dispenser of claim 8, wherein each of the flexible arms comprises a rounded protrusion.
 10. The soap dispenser of claim 8, wherein the inner cavity is configured to bend at least one of the flexible arms more than another one of the flexible arms.
 11. The soap dispenser of claim 1, wherein the inner cavity comprises a generally eccentric-circular shape.
 12. The soap dispenser of claim 1, wherein the impeller comprises a bore.
 13. The soap dispenser of claim 12, further comprising an actuation mechanism connected to the impeller bore.
 14. The soap dispenser of claim 1, wherein the pump is configured to generate a negative pressure that is less than a pressure at the aspirator outlet.
 15. The soap dispenser of claim 1, wherein the pump further comprises an inlet pocket near a pump inlet and an outlet pocket near a pump outlet, the inlet pocket being larger than the outlet pocket.
 16. The soap dispenser of claim 1, wherein the pump further comprises a pocket configured to transition between a first configuration and a second configuration, the pocket being larger in the first configuration than in the second configuration.
 17. The soap dispenser of claim 1, further comprising a flow-enhancing member in fluid communication with the inner cavity of the pump body, the flow-enhancing member disposed downstream from the pump.
 18. The soap dispenser of claim 17, wherein the flow-enhancing member is a screen.
 19. The soap dispenser of claim 17, wherein the flow-enhancing member is configured to provide a back pressure.
 20. The soap dispenser of claim 1, wherein the discharge nozzle is a duckbill valve.
 21. The soap dispenser of claim 1, further comprising a holding chamber disposed downstream of the aspirator, the holding chamber configured to store the soap foam for a period of time.
 22. A method of dispensing foaming liquid soap from a soap dispenser, the method comprising: drawing a flow of liquid soap from a reservoir and through a first inlet of an aspirator; drawing a flow of ambient air through a second inlet of the aspirator; generating soap foam in a channel of the aspirator; drawing the soap foam from an aspirator outlet and through an inlet of a pump, the pump comprising a body and an impeller, the impeller disposed in an inner cavity of the body; and discharging a portion of the soap foam from a nozzle.
 23. The method of claim 22, further comprising drawing the soap foam into a holding chamber, the holding chamber disposed downstream from the aspirator.
 24. The method of claim 23, further comprising storing the soap foam in the holding chamber for a period of time.
 25. The method of claim 22, wherein drawing the flow of liquid soap from the reservoir and through the first inlet comprises drawing the flow of liquid soap through a valve.
 26. The method of claim 22, further comprising generating a negative pressure within the aspirator channel relative to ambient.
 27. The method of claim 22, further comprising generating a region of pressure near the second inlet that is less than a region of pressure near the first inlet.
 28. The method of claim 22, further comprising driving the impeller, the impeller including a central body portion and a plurality of flexible arms.
 29. The method of claim 28, wherein driving the impeller comprises moving a pocket between a first configuration and a second configuration, the pocket being larger in the first configuration than in the second configuration.
 30. The method of claim 28, wherein driving the impeller comprises moving each of the flexible arms between a first configuration and a second configuration, wherein each of the flexible arms is more bent in the first configuration than in the second configuration.
 31. The method of claim 22, further comprising generating a negative pressure within the inner cavity relative to ambient.
 32. The method of claim 21, further comprising generating a pressure within the inner cavity that is less than the pressure at the aspirator outlet.
 33. The method of claim 22, further comprising discharging the soap foam from an outlet of the pump and through a flow-enhancing member.
 34. The method of claim 33, wherein discharging the soap foam through the flow-enhancing member further comprises generating a back pressure. 